USAFE electrical fire suppression systems use the patented detection tubing which is installed throughout the enclosure and connected to the cylinder valve. The tubing is then charged with nitrogen and this pressure is utilized to hold back the extinguishant in the cylinder.
When a high temperature or fire occurs then the pressurized tubing will burst and the extinguishant will be deployed directly from the burst hole onto the fire.
This effectively means the fire has formed the discharge nozzle so it is always exactly in the right location.
A switch is also added to the system and is held closed by the pressure. Should the tubing burst or the pressure be lost for any reason then the switch will open and this signal can be used to raise an alarm.